Devices, systems, and methods for measuring fluid level using radio-frequency (rf) localization

ABSTRACT

Disclosed herein are devices, systems, and methods for accurately determining fluid level using Ultra Wideband (UWB) positioning or localization. UWB utilizes a radio-frequency (RF) technology to enable the accurate measurement of the time-of-flight of a radio signal and UWB positioning can operate in Time-Difference-of-Arrival (TDoA) mode, Two-Way-Ranging (TWR) mode, and Phase-Difference-of-Arrival (PDoA) mode. The systems disclosed herein include multiple anchor devices having a UWB antenna(s) and positioned in fixed location(s) over the fluid to be measured. The anchor devices serve as reference points for UWB communication with a remote float device, which emits RF signals and floats on the surface of the fluid to be measured. The anchor devices may include, or be in communication with, a processor which receives and/or measures RF signals, generates timestamps, calculates distance(s) between the remote float device and an anchor device, calculates fluid level, calculates an angle-of-arrival (AoA), or any combination thereof.

PRIORITY

The present application a) is related to, claims the priority benefitof, and is a U.S. bypass continuation of, PCT Patent Application SerialNo. PCT/US2022/015873, filed Feb. 9, 2022, which is related to, andclaims the priority benefit of, 1) U.S. Nonprovisional patentapplication Ser. No. 17/324,906, filed May 19, 2021, which is relatedto, and claims the priority benefit of, U.S. Provisional PatentApplication Ser. No. 63/147,346, filed Feb. 9, 2021, and 2) U.S.Provisional Patent Application Ser. No. 63/147,346, filed Feb. 9, 2021,and b) is related to, claims the priority benefit of, and is a U.S.continuation-in-part patent application of, U.S. Nonprovisional patentapplication Ser. No. 17/324,906, filed May 19, 2021 and issued as U.S.Pat. No. 11,248,946 on Feb. 15, 2022, which is related to, and claimsthe priority benefit of, U.S. Provisional Patent Application Ser. No.63/147,346, filed Feb. 9, 2021. The contents of each of the foregoingpatents and patent applications are incorporated herein directly and byreference in their entirety.

BACKGROUND

Various approaches have been used to measure the level of fluidcontained in a container, such as within a wastewater wet well, sumppit, or other contained space. For example, in one approach, a float,such as an air-tight buoyant container, is suspended in a fluid andattached to a rod. The rod is attached at a swivel point that allows thefloat to move up and down as it floats on the surface of the fluid. Theswivel point is also connected to a device, such as a variable resistor,that allows the position of the swivel point to be measured. A change inthe swivel point's measured position then corresponds to a change influid level, which allows the fluid's depth to be known. However, thisapproach to measuring fluid level by using a float has severaldrawbacks, including having numerous moving parts prone to failure, asmall-range depth measuring capability, and other limitations.

Other approaches are presently available for fluid level measurement.Ultrasonic fluid measuring involves injecting an ultrasonic wave towardsthe fluid's surface. A transducer then captures the ultrasonic wavereflected back by the fluid's surface and measures time-of-flight tocalculate the fluid's depth. However, an ultrasonic fluid measuringsystem can be affected by changes in environmental conditions such astemperature and the presence of dust or vapor, resulting in inaccuratefluid level measurements.

Radar fluid measuring is another method which operates similarly to theultrasonic measuring method by injecting a radio-frequency (RF)microwave toward the fluid's surface. A transducer then captures the RFmicrowave reflected by the fluid's surface and measures time-of-flightto calculate the fluid's depth. However, radar fluid measuring alsosuffers from inaccuracies caused by RF reflections off objects in theenvironment, which are often difficult to distinguish from the desiredsignal.

In another approach, a submersible pressure transducer configured tomeasure hydrostatic pressure may be submerged directly in the fluid tobe measured. The height of the fluid column above the transducer is thencalculated, which indicates the fluid's depth. However, these pressuretransducers often suffer from clogs in the sensor element orifice andexternal vent tube, which require frequent servicing to correct. In yetanother approach, determining the position of one device relative toanother, known as positioning, is achievable by measuring thetime-of-flight of RF signals between the devices. Since the speed of RFwaves is constant (the speed of light), and the RF wave's travel time ismeasurable, calculating distances can be more accurately achieved.

Ultra Wideband (UWB) is an RF technology based on the IEEE 802.15.4a and802.15.4z standards that can enable the very accurate measure of a RFsignal's time-of-flight, leading to real time, centimeter-level accuracydistance measuring and/or positioning between UWB transceivers.According to the FCC, UWB is any signal that occupies a wide bandwidth(greater than 20% of the center frequency or 500 MHz) and utilizes thespectrum between 3.1 and 10.6 GHz. Additionally, UWB uses short pulseson the order of 10-1000 picoseconds. In theory, the time-of-flight ofany RF signal can be measured. However, in practice, a wide-band RFsignal provides a more accurate time measurement than narrowband signalssuch as Bluetooth, Bluetooth Low Energy (BLE) and/or Wi-Fi. It wouldthus be desirable to utilize the approach of positioning or localizingone device relative to another, combined with the centimeter-levelaccuracy of RF, or UWB technology, to provide an improved system andmethod for more accurately measuring the level of a fluid.

BRIEF SUMMARY OF THE INVENTION

The present disclosure includes disclosure of a system for measuring afluid level, comprising: at least one anchor device having aradio-frequency (RF) antenna positioned at a fixed location over asurface of a fluid; at least one remote float device configured to emitat least one RF signal and configured to float on the surface of a fluidto be measured; and a processor in operable communication with the atleast one anchor device, the processor configured to: receive the atleast one RF signal emitted from the at least one remote float device;analyze the at least one RF signal received by the RF antenna; andcalculate a location of the at least one remote float device based uponthe analyzed at least one RF signal received by the RF antenna, whereinthe location of the at least one remote float device corresponds to alevel of the fluid.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to calculate a level of the fluid, basedupon the calculated location of the at least one remote float device.The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to: measure a time-of-flight of the atleast one RF signal between the at least one remote float device and theat least one anchor device; and calculate level of the fluid based onthe fixed location of the at least one anchor device and thetime-of-flight of the at least one RF signal. The present disclosurealso includes disclosure of a system, wherein the processor is furtherconfigured to: calculate location of the at least one remote floatdevice based on the time-of-flight of the at least one RF signal and thefixed location of the at least one anchor device.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to: receive the at least one RF signalon a plurality of RF antennas; and measure a phase-difference-of-arrivalof the at least one RF signal received from each of the plurality of RFantennas.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to: calculate the location of the atleast one remote float device in a plurality of dimensions based on thetime of flight, the phase-difference-of-arrival, and the fixed locationof the at least one anchor device. The present disclosure also includesdisclosure of a system, wherein the processor is further configured torecognize a predetermined threshold condition; and emit a RF signal inresponse to meeting the predetermined threshold condition. The presentdisclosure also includes disclosure of a system, wherein meeting thepredetermined threshold condition includes one selected from the groupof: receipt of a message generated by either the at least one anchordevice or by the at least one remote float device; movement of the atleast one remote float device; receipt of auxiliary sensor input;diagnostic events; and passage of a predetermined time interval.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to signal a pump control system to pumpthe fluid in response to the fluid level being greater than a thresholdvalue.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to receive location data identifying thefixed position of the at least one anchor device; receive a unique ID ofthe at least one remote float device; and store the location data andunique ID of the at least one remote float device. The presentdisclosure also includes disclosure of a system, further comprising atleast three anchor devices, wherein the processor is further configuredto: synchronize time on each of the at least three anchor devices;determine a time-of-flight of an RF signal sent between the at least oneremote float device and each of the at least three anchor devices;measure a time difference-of-arrival (TDoA) based on times the RF signalis received by each of the at least three anchor devices; and calculatethe time-of-flight based on the TDoA measurement.

The present disclosure also includes disclosure of a system, wherein theprocessor is positioned within one of the at least one anchor devices.The present disclosure also includes disclosure of a system, wherein theRF antenna comprises an UWB antenna. The present disclosure alsoincludes disclosure of a system, wherein the processor is in a remotelocation and communicates with either the at least one remote floatdevice, or the at least one anchor device, using alternate RFcommunication, such as, but not limited to, Wi-Fi, BLE, and/or sub-GHz.The present disclosure also includes disclosure of a system, furthercomprising a wired power connection, wherein the at least one anchordevice and the at least one remote float device communicate using thewired power connection. The present disclosure also includes disclosureof a system, wherein the at least one remote float device furthercomprises at least one auxiliary sensor selected from the groupconsisting of: a microphone, a pressure transducer, and a camera.

The present disclosure includes disclosure of a system for measuring afluid level using two-way RF communication modes, comprising: at leastone anchor device having a radio-frequency (RF) antenna positioned at afixed location over a surface of a fluid; at least one remote floatdevice configured to emit one or more RF signals and configured to floaton the surface of the fluid to be measured; and a processor in operablecommunication with the at least one anchor device, the processorconfigured to: receive at least one RF signal emitted from the at leastone remote float device; analyze the at least one RF signal received bythe RF antenna; and calculate a location of the at least one remotefloat device based upon a time-of-flight or an angle-of-arrival (AoA) ofthe analyzed at least one RF signal received by the RF antenna, whereinthe location of the at least one remote float device corresponds to alevel of the fluid. The present disclosure also includes disclosure of asystem, wherein the processor is further configured to calculate anangle, in at least one plane, of the at least one remote float devicerelative to the at least one anchor device. The present disclosure alsoincludes disclosure of a system, wherein the processor is furtherconfigured to calculate an angle, in at least one plane, of the at leastone anchor device relative to the at least one remote float device.

The present disclosure also includes disclosure of a method, formeasuring fluid level, comprising: positioning at least one anchordevice at a fixed location over a surface of a fluid, the at least oneanchor device operably coupled to at least one UWB antenna therein;floating at least one remote float device on the surface of the fluid,the at least one remote float device configured to emit RF signals;receiving at least one RF signal at a processor; generating one or moremeasurements, at the processor, in response to receipt of the at leastone RF signal, the one or more measurements comprising a time-of-flightof the at least one RF signal between the at least one remote floatdevice and the at least one anchor device, an angle of arrival, or acombination thereof; calculating, based upon the one or moremeasurements, at least one of: i) a level of the fluid; ii) a distancebetween the at least one remote float device and the at least one anchordevice; and iii) an angle in at least one plane of the at least oneremote float device relative to the at least one anchor device; andproviding a measurement of fluid level based upon the calculating of theone or more measurements.

The present disclosure also includes disclosure of a method, wherein thetime-is-flight is measured based on a time value encoded in the at leastone RF signal, wherein the at least one RF signal is generated by the atleast one remote float device, the at least one anchor device, or acombination thereof. The present disclosure also includes disclosure ofa system for measuring a fluid level, comprising at least one anchordevice having at least one radio-frequency (RF) antenna positioned at afixed location over a surface of a fluid to be measured, at least oneremote float device configured to emit at least one RF signal andconfigured to float on the surface of a fluid to be measured, and aprocessor in operable communication with the at least one anchor device,the processor configured to receive the at least one RF signal from theat least one RF antenna, emitted from the at least one remote floatdevice, analyze the at least one RF signal from the at least one RFantenna, measure a time-of-flight of the at least one RF signal betweenthe at least one remote float device and the at least one anchor device,calculate a location of the at least one remote float device based uponthe analyzed at least one RF signal received by the at least one RFantenna, wherein the location of the at least one remote float devicecorresponds to a level of the fluid.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to calculate a level of the fluid, basedupon the calculated location of the at least one remote float device.The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to calculate a level of the fluid basedon the fixed location of the at least one anchor device and thetime-of-flight of the at least one RF signal. The present disclosurealso includes disclosure of a system, wherein the processor is furtherconfigured to calculate location of the at least one remote float devicebased on the time-of flight of the at least one RF signal and the fixedlocation of the at least one anchor device. The present disclosure alsoincludes disclosure of a system, wherein the processor is furtherconfigured to receive the at least one RF signal on a plurality of RFantennas, and measure a phase-difference-of-arrival of the at least oneRF signal received from each of the plurality of RF antennas. Thepresent disclosure also includes disclosure of a system, wherein theprocessor is further configured to calculate the position of the atleast one remote float device in a plurality of dimensions based on thetime-of-flight and the phase-difference-of-arrival.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to recognize a predetermined thresholdcondition, and emit a RF signal in response to meeting the predeterminedthreshold condition. The present disclosure also includes disclosure ofa system, wherein meeting the predetermined threshold condition includesone selected from the group of receipt of a message generated by eitherthe at least one anchor device or by the at least one remote floatdevice, movement of the at least one remote float device, receipt ofauxiliary sensor input, diagnostic events, and passage of apredetermined time interval. The present disclosure also includesdisclosure of a system, wherein the processor is further configured tosignal a control system in response to the fluid level being greaterthan or less than a threshold value. The present disclosure alsoincludes disclosure of a system, wherein the processor is furtherconfigured to receive location data identifying the fixed position ofthe at least one anchor device, receive a unique ID of the at least oneremote float device, and store the location data and unique ID of the atleast one remote float device. The present disclosure also includesdisclosure of a system, further comprising at least three anchordevices, wherein the processor is further configured to synchronize timeon each of the at least three anchor devices, and measure a timedifference-of-arrival (TDoA) based on times the at least one RF signalis received by each of the at least three anchor devices. The presentdisclosure also includes disclosure of a system, wherein the processoris positioned within one of the at least one anchor devices. The presentdisclosure also includes disclosure of a system, wherein the at leastone RF antenna comprises an UWB antenna. The present disclosure alsoincludes disclosure of a system, wherein the processor is in a remotelocation and communicates with either the at least one remote floatdevice, or the at least one anchor device, using alternate RFcommunications consisting of Wi-Fi, BLE, and/or sub-GHz. The presentdisclosure also includes disclosure of a system, wherein the at leastone remote float device further comprises at least one auxiliary sensorselected from the group consisting of a microphone, a pressuretransducer, and a camera.

The present disclosure also includes disclosure of a system formeasuring a fluid level using two-way RF communication modes, comprisingat least one anchor device having at least one radio-frequency (RF)antenna positioned at a fixed location over a surface of a fluid to bemeasured, at least one remote float device configured to emit one ormore RF signals and configured to float on the surface of the fluid tobe measured, and a processor in operable communication with the at leastone anchor device, the processor configured to receive at least one RFsignal from the at least one RF antenna, emitted from the at least oneremote float device, analyze the at least one RF signal from the atleast one RF antenna, and calculate a location of the at least oneremote float device based upon a time-of-flight and/or aphase-difference-of-arrival (PDoA) of the analyzed at least one RFsignal received by the at least one RF antenna, wherein the location ofthe at least one remote float device corresponds to a level of thefluid. The present disclosure also includes disclosure of a system,wherein the processor is further configured to calculate an angle, in atleast one plane, of the at least one remote float device relative to theat least one anchor device. The present disclosure also includesdisclosure of a system, wherein the processor is further configured tocalculate an angle, in at least one plane, of the at least one anchordevice relative to the at least one remote float device.

The present disclosure also includes disclosure of a system formeasuring a fluid level, comprising at least one anchor device having afirst radio-frequency (RF) transceiver positioned at a fixed locationover a surface of a fluid to be measured, at least one remote floatdevice having a second radio-frequency (RF) transceiver configured tofloat on the surface of the fluid to be measured, a transceiver coupledto the RF antenna, configured to receive the at least one RF signal fromthe at least one RF antenna, a transceiver coupled to the at least oneRF antenna configured to extract packets from the at least one RFsignal, a processor in operable communication with at least one of thefirst RF transceiver and the second RF transceiver, the processorconfigured to receive the at least one packet from the second RFtransceiver, transmitted from the at least one remote float device,analyze the at least one packet from the second RF transceiver, measurea time-of-flight of the at least one RF signal between the at least oneremote float device and the at least one anchor device using the RFpackets, calculate a location of the at least one remote float devicebased upon the time-of-flight, wherein the location of the at least oneremote float device corresponds to a level of the fluid.

The present disclosure also includes disclosure of a system, wherein theat least one remote float device further comprises a chemical-resistantcoating to prevent corrosion and adhesion of foreign material to theremote float device. The present disclosure also includes disclosure ofa system, wherein the chemical-resistant coating is configured toprevent the adhesion of grease to the remote float device. The presentdisclosure also includes disclosure of a system, wherein the at leastone remote float device further comprises a mechanical housing selectedfrom the group consisting of an air-tight housing, a capture ring, astabilizing fin, and a counter-weight. The present disclosure alsoincludes disclosure of a system, wherein the processor is furtherconfigured to adjust an interval at which the RF signals are emitted bythe at least one remote float device based on a rate of change of thelevel of the fluid. The present disclosure also includes disclosure of asystem, wherein the at least one remote float device or the at least oneanchor device is configured to optimize RF transmitting power to reducereflections and extend battery life. The present disclosure alsoincludes disclosure of a system, wherein the processor is furtherconfigured to signal a pump control system to pump the fluid in responseto remaining space in the container being greater than or less than athreshold value. The present disclosure also includes disclosure of asystem, wherein the processor is further configured to notify anexternal control system that the level of the fluid has changed.

The present disclosure also includes disclosure of a system, wherein theprocessor is further configured to notify an external control system inresponse to receipt of a message from the at least one anchor device orthe at least one remote float device. The present disclosure alsoincludes disclosure of a system, wherein the processor is also inoperable communication with the at least one anchor device or the atleast one remote float device using an alternate RF communicationscomprising Wi-Fi, BLE, or sub-GHz antenna. The present disclosure alsoincludes disclosure of a system, wherein the at least one remote floatdevice is further configured to detecting activity of pumps of the pumpcontrol system by analyzing acoustic characteristics from a microphonepositioned relative to the pumps, and transmitting data from themicrophone to the processor. The present disclosure also includesdisclosure of a system, wherein the at least one remote float device isfurther configured to operate a pressure transducer to detect acondition of the at least one remote float device as being submergedunder the surface of the fluid. The present disclosure also includesdisclosure of a system, wherein the at least one remote float devicefurther comprises at least one auxiliary sensor selected from the groupconsisting of an accelerometer, a gyroscope, and a magnetometer. Thepresent disclosure also includes disclosure of a system, wherein the atleast one remote float device further comprises an accelerometer, the atleast one remote float device further configured to operate theaccelerometer to detect a condition of the at least one remote floatdevice as not being level with the surface of the fluid. The presentdisclosure also includes disclosure of a system, wherein the processoris further configured to obtain telemetry data and instruct saidtelemetry data to be stored within an external data storage system. Thepresent disclosure also includes disclosure of a system, wherein thetelemetry data is selected from the group consisting of fluid level,fluid overflow, fluid temperatures, stored power levels, and microphonedata.

The present disclosure also includes disclosure of a method of operatinga system for measuring a fluid level, the method comprising the steps offloating at least one remote float device on a surface of a fluid to bemeasured, the at least one remote float device comprising at least oneradio-frequency transceiver configured to transmit and receiveradio-frequency (RF) signals, positioning at least one anchor device ata fixed location over the surface of the fluid to be measured, the atleast one anchor device comprising at least one radio-frequencytransceiver configured to transmit and receive RF signals, capturingtransmission and reception timestamps of the RF signals transmittedbetween the at least one anchor device and the at least one remote floatdevice, exchanging the transmission and reception timestamps between theat least one anchor device and the at least one remote float device in atwo-way ranging round to calculate a time-of-flight of the RF signals,and calculating a distance between each at least one anchor device andthe at least one remote float device based upon the time-of-flight ofthe RF signals. The present disclosure also includes disclosure of amethod, further comprising the step of calculating a level of the fluidbased upon the fixed location of each at least one anchor device and thecalculated distance between each at least one anchor device and the atleast one remote float device. The present disclosure also includesdisclosure of a method, further comprising measuring at least onephase-difference-of-arrival (PDoA) of the RF signals as the RF signalsare received by a plurality of antennas within each at least one anchordevice, calculating at least one angle of arrival (AoA), in at least oneplane, of each at least one remote float device relative to each atleast one anchor device based upon the PDoA measurements, andcalculating a position of each at least one remote float device relativeto each at least one anchor device using the calculated distance and thecalculated at least one angle of arrival, where the positions correspondto the surface of the fluid. The present disclosure also includesdisclosure of a method, further comprising calculating a level of thefluid based upon the fixed location of each at least one anchor deviceand the calculated positions of each at least one remote float devicerelative to each at least one anchor device.

The present disclosure also includes disclosure of a method formeasuring fluid level, comprising positioning at least one anchor deviceat a fixed location over a surface of a fluid to be measured, the atleast one anchor device operably coupled to at least one UWB antennatherein, floating at least one remote float device on the surface of thefluid to be measured, the at least one remote float device configured toemit RF signals, receiving at least one RF signal from the RF antenna ata processor, generating one or more measurements, at the processor, inresponse to receipt of the at least one RF signal, the one or moremeasurements comprising a time-of-flight of the at least one RF signalbetween the at least one remote float device and the at least one anchordevice, an angle of arrival, or a combination thereof, calculating,based upon the one or more measurements, at least one of: i) a level ofthe fluid; and ii) a distance between the at least one remote floatdevice and the at least one anchor device; and iii) an angle in at leastone plane of the at least one remote float device relative to the atleast one anchor device, and providing a measurement of fluid levelbased upon the calculating of the one or more measurements. The presentdisclosure also includes disclosure of a method, wherein thetime-is-flight is measured based on a time value encoded in the at leastone RF signal from the RF antenna, wherein the at least one RF signal isgenerated by the at least one remote float device, the at least oneanchor device, or a combination thereof.

The present disclosure also includes disclosure of a method of operatingfluid level measurement system configured to measure a distance betweenat least one anchor device and at least one remote float device, themethod comprising the steps of floating the at least one remote floatdevice on a surface of a fluid to be measured, positioning the at leastone anchor device at a fixed location over the surface of the fluid tobe measured, transmitting packets from the at least one remote floatdevice to the at least one anchor device, transmitting the packets fromthe at least one anchor device back to the at least one remote floatdevice after a specified length of time, calculating the time requiredfor the packets to be transmitted to the at least one anchor device andback to the at least one remote float device using two-way ranging, andcalculating a distance to the least one remote float device based uponthe two-way ranging, wherein the distance of the at least one remotefloat device corresponds to a level of the fluid.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed embodiments and other features, advantages, anddisclosures contained herein, and the matter of attaining them, willbecome apparent and the present disclosure will be better understood byreference to the following description of various exemplary embodimentsof the present disclosure taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1A illustrates a block diagram of an exemplary system for measuringfluid level using UWB positioning in Time-Difference-of-Arrival (TDoA)mode;

FIG. 1B illustrates a schematic of an exemplary system for measuringfluid level using UWB positioning in Two-Way-Ranging (TWR) mode;

FIG. 1C illustrates a schematic of an exemplary system for measuringfluid level using UWB positioning in Two Way Ranging plusPhase-Difference-of-Arrival (TWR+PDoA) mode;

FIG. 2 illustrates a diagram of an exemplary system for measuring fluidlevel using UWB positioning in TWR mode;

FIG. 3 illustrates a diagram of an exemplary system for measuring fluidlevel using UWB positioning in TDoA mode;

FIG. 4 illustrates a diagram of an exemplary system for measuring fluidlevel using UWB positioning in TWR+PDoA mode;

FIG. 5A illustrates a block diagram of an exemplary remote float device;

FIG. 5B illustrates a block diagram of an exemplary remote float device;

FIG. 5C illustrates a perspective view of an exemplary remote floatdevice;

FIG. 5D illustrates a bottom perspective view of an exemplary remotefloat device;

FIG. 6A illustrates a block diagram of an exemplary anchor device;

FIG. 6B illustrates a perspective view of an exemplary anchor device;

FIG. 7 illustrates a diagram of an exemplary system for measuring fluidlevel in a wastewater well using UWB positioning;

FIG. 8 illustrates a diagram of an exemplary system for measuring fluidlevel in a sump pump pit using UWB positioning;

FIG. 9 illustrates a diagram of an exemplary system for measuring fluidlevel in a river using UWB positioning;

FIG. 10 illustrates an exemplary method of measuring fluid level usingUWB positioning;

FIG. 11 illustrates an exemplary logic flow diagram for a smartphoneapplication that may communicate with a system for measuring fluid levelusing UWB positioning; and

FIG. 12 illustrates an exemplary logic flow diagram of communicationsbetween an anchor device and a remote float device.

As such, an overview of the features, functions and/or configurations ofthe components depicted in the various figures will now be presented. Itshould be appreciated that not all of the features of the components ofthe figures are necessarily described and some of these non-discussedfeatures (as well as discussed features) are inherent from the figuresthemselves. Other non-discussed features may be inherent in componentgeometry and/or configuration. Furthermore, wherever feasible andconvenient, like reference numerals are used in the figures and thedescription to refer to the same or like parts or steps. The figures arein a simplified form and not to precise scale.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the embodimentsillustrated in the drawings, and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of this disclosure is thereby intended.

The present disclosure includes various devices, systems, and methodsfor determining fluid level using radio-frequency (RF) positioning. Insome embodiments, Ultra Wideband (UWB) localization may be used, notingthat any RF technology or signal (not just UWB), including those whichmay be developed in the future, may also be used. UWB is a RF technologywhich enables the accurate measurement of the time-of-flight of a radiosignal, thus providing centimeter-level accuracy and providing accuratefluid level measurements. The radio signals may contain messages, alsoknown packets. The methods disclosed herein may be used to accuratelymeasure fluid level in a container, or in another other body of water.The term ‘container’ may describe anything that holds fluids, such as,but not limited to, vessels, tanks, pits, and bodies of water such asoceans, seas, lakes, rivers, and canals, etc. These methods also involvecommunications between one-to-one devices or one-to-many devices to moreaccurately determine positioning and/or localization. UWB positioning orlocalization can operate in various modes, such as, but not limited toTime-Difference-of-Arrival (TDoA), Two-Way Ranging (TWR), andPhase-Difference-of-Arrival (PDoA), as will be described in furtherdetail below. These modes may also be applicable to RF positioning orlocalization in combination with other technologies such as, but notlimited to, Wi-Fi and/or BLE.

In one embodiment, an exemplary system for determining fluid level usingUWB positioning in TDoA mode is shown generally in FIG. 1A. In this TDoAmode embodiment, multiple anchor devices 14 (also called “anchors”herein) may be positioned in multiple known locations to serve asreference points for UWB communication with a remote float device 13.The anchor devices 14 may be time-synchronized to provide a clock basefor time measurements. The remote float device 13 emits an UWB signal,and each anchor device 14 then timestamps the signal as it is received.The timestamps from each anchor device 14 in the system are sent to aprocessor, such as within a controller, where the TDoA signals betweenthe anchors 14 are used in an algorithm which computes the remote floatdevice's 13 position in multiple dimensions. The processor and/orcontroller may be one of the system's own anchor devices 14, and/or itmay be separate from the anchor devices 14, while still being inoperable communication with the anchor devices 14.

In another embodiment, an exemplary system for determining fluid levelusing UWB positioning in TWR mode is shown in FIG. 1B. In this TWR modeembodiment, an anchor device 14 and a remote float device 13 utilizetwo-way UWB communications. This TWR mode measures the time-of-flight ofat least two messages exchanged between a remote float device 13 and ananchor device 14. The remote float device 13 may initiate an UWB signalexchange by emitting a first message. In this case, time synchronizationbetween the anchor 14 and remote float device 13 is unnecessary becausethe timestamps of message transmission and reception are encoded in themessages as they are exchanged. The anchor device 14 uses the encodedtimestamps to calculate round-trip time to the remote float device 13,which is used to derive the distance between itself and the remote floatdevice 13. In an alternative configuration, the anchor device 14 caninitiate an exchange by emitting the first message, which then allowsthe remote float device 13 to calculate the distance between itself andthe anchor device 14. In another embodiment, multiple anchor devices 14may be used with one or more remote float device(s) 13 in a TWR systemto provide information on a remote float device's 13 positioning inmultiple dimensions.

In another embodiment, an exemplary system for determining fluid levelusing UWB positioning in TWR+PDoA mode is shown in FIG. 1C. In thisTWR+PDoA mode embodiment, the distance between an anchor device 14having multiple antennas, and a remote float device 13, may bedetermined using TWR. This system may provide a measure of the angle (orangle-of-arrival (AoA)) between peer devices, in addition to a measureof the distance between remote float devices 13. The AoA is derived bymeasuring the PDoA of the RF signal as received by a plurality ofantennas. The RF signal will reach each antenna at a slightly differenttime, resulting in a measurable phase difference. The phase differenceis used to derive the AoA, or bearing, of the RF signal. If at leastthree antennas are used in a PDoA architecture, a remote float device's13 positioning can be determined in three dimensions.

FIG. 2 illustrates an exemplary embodiment of a system for determiningfluid level in a container 11 using UWB positioning in TWR mode. Thesystem may include a remote float device 13 in UWB communication with ananchor device 14. The anchor device 14 may have a UWB antenna and bemounted in a fixed location above the fluid level 12 in a container 11.The remote float device 13 emits a UWB signal and floats on the surfaceof the fluid 12, as shown in FIG. 1. The distance between the anchordevice 14 and the remote float device 13 can be calculated using UWBpositioning or localization techniques. This distance, and the anchordevice's 14 known height above the bottom of the container, may then beused to calculate the level of fluid 12. The anchor device 14 uses itsUWB antenna, or UWB antenna array, to receive the RF signal and it maythen operate as a processor to calculate the distance (shown indimension 2A) between itself and the remote float device 13 using TWR.In this embodiment, distance dimension 2A also approximates the distancedimension 2B, as shown in FIG. 2. With the anchor device's 14 knownheight above the bottom of the container 11 (shown as dimension 2D), thelevel of the fluid 12 (shown as dimension 2C) may then be calculated bysubtracting dimension 2B from 2D. Resulting dimension 2C then providesan accurate measurement of the level of the fluid 12 in container 11. Insome embodiments, the level of the fluid 12 may also be used todetermine the depth of the fluid 2C.

FIG. 3 illustrates an exemplary embodiment of a system for determiningfluid level in a container 11 using UWB positioning in TDoA mode. Thesystem may include multiple UWB anchor devices 14, each with its owncorresponding UWB antenna. The anchor devices 14 may be mounted in fixedlocations above the fluid level 12 in a container 11. One or more remotefloat device(s) 13 may be floating on the surface of the fluid 12. Theuse of more than one remote float device 13 adds redundancy to thesystem. The system may operate in TDoA mode in communication with aprocessor and/or controller. In some embodiments, at least one of theanchor devices 14 may operate as a processor and/or controller and/ormay be in operable communication with a processor and/or controller. Theprocessor and/or controller may calculate the position of the remotefloat device 13 relative to the anchor devices 14 by determiningdistances 3A, 3B, and 3C, using TDoA, from which dimension 3D may bederived, as shown in FIG. 3. The known distances may also be used in acalculation to determine the position of each remote float device 13 inmultiple dimensions. The calculated position of the remote floatdevice(s) 13, and each anchor device's 14 known position relative to thebottom of the container 11, is used to calculate the level of the fluid12. With each anchor devices' 14 known height above the bottom of thecontainer 11 (shown as dimension 3F), the level of the fluid 12 (shownas dimension 3E) is calculated by subtracting dimension 3D from 3F.Resulting dimension 3E then provides an accurate measurement of thelevel of the fluid 12 in container 11.

FIG. 4 illustrates an exemplary embodiment of a system for determiningfluid level in a container 11 using UWB positioning in TWR+PDoA mode.The system may include at least one UWB anchor device 14 having aplurality of UWB antennas, or a UWB antenna array. The anchor device 14may be mounted in a fixed location above the fluid level 12 in acontainer 11. One or more remote float device(s) 13 may be floating onthe surface of the fluid 12. The plurality of UWB antennas in the atleast one anchor device 14 may provide information on the positioning ofthe remote float device(s) 13 in multiple dimensions. The anchor device14 may calculate the position of the remote float device(s) 13 relativeto the anchor 14 using TWR+PDoA mode. The PDoA of the RF signal ismeasured as received by a plurality of antennas. The position of theantennas relative to each other within the anchor device 14 is criticalto ensure accurate measurement of PDoA. The separation distance of theantennas must be chosen based on the wavelength of the RF signal. Todetermine position in three dimensions, at least three antennas arerequired, and at least one antenna is positioned in a separate plane oroffset in at least one axis in the same plane. The PDoA may be measuredwith a plurality of antenna pairs, to derive an AoA. The AoA for one ofthe planes is illustrated as theta (0) in this example. The AoA for allplanes and the measured distance provides a 3D vector (or coordinate)that allows for the calculation of dimension 4A, as shown in FIG. 4.With the anchor device's 14 known height above the bottom of thecontainer 11 (shown as dimension 4C), the level of the fluid 12 (shownas dimension 4B) is calculated by subtracting dimension 4A from 4C.Resulting dimension 4B then provides an accurate measurement of thelevel of the fluid 12 in container 11.

In any of the examples described herein, it should be appreciated thatthe anchor device(s) 14 and/or remote float device(s) 13 may eachcomprise its own processor and/or controller and/or may share processingresponsibility for calculating, analyzing, and/or determining the fluidlevel 12. In some examples, one or more of the anchor device(s) 14 mayinitiate contact with the remote float device(s) 13. Alternatively, orin addition, the remote float device(s) 13 may initiate contact with theanchor device(s) 14. After contact is initiated, the time of flightand/or angle may be calculated by the remote float device(s) 13, anchordevice(s) 14, processors, and/or any combination thereof. For example,the anchor device(s) 14 may calculate the angle of a remote float device13 relative to itself. Likewise, the remote float device 13 maycalculate the angle of an anchor device relative to itself. Furthermore,the fluid level 11 may be calculated by the anchor device(s) 14, remotefloat device(s) 13, processors, and/or any combination thereof. Finally,the calculated fluid level may be output by the remote float device(s)13, anchor device(s) 14, processors, and/or any combination thereof.

FIG. 5A illustrates an exemplary UWB positioning remote float device 13powered by a battery 58. The remote float device 13 may include, atleast, a processor 50 operably coupled to: UWB circuitry 51 connected toan UWB antenna 52; alternative RF communications 53 connected to anantenna 54; an inertial measurement unit (IMU) 55; a temperature sensor56; and power management 57 connected to battery 58. The processor 50may be suitable for executing algorithms and/or processing data inaccordance with operating logic. The UWB circuitry 51 may contain RFcomponents, ICs, and passive components, or a module to implement an UWBtransmitter and/or transceiver. The alternate RF communications 53 mayalso include RF components, ICs, and passive components, and/or a moduleto implement an alternate RF communications transceiver, such as, butnot limited to, a Wi-Fi, BLE, and/or sub-GHz transceiver. The alternateRF communication's 53 transceiver may also be used as an additional RFcommunication link to an anchor device 14 and/or to third-party devices,such as a smartphones, etc. The IMU 55 may be used to measure and reporta body's specific force, angular rate, and/or orientation using acombination of accelerometers, gyroscopes, and sometimes magnetometers.For example, the IMU 55, or other auxiliary sensor inputs (microphones,pressure sensors, cameras, etc.), may be used to determine faultconditions, such as a condition where the remote float device 13 is notlevel with the surface of the fluid 12, which may indicate it is stuck.The temperature sensor 56 may be used to compensate for the effects oftemperature on individual components in the system or in calculationsperformed in the processor 50. The power management 57 ensures the othercomponents within the remote float device 13 receive adequate power, andalso monitors the health and remaining capacity of the battery 58.

In addition to the IMU 55, auxiliary sensors may also be utilized in theremote float device 14 to provide additional trigger criteria and inputsto the processor and/or controller. Additional auxiliary sensors mayinclude, but are not limited to, audible sensors such as microphones,pressure sensors such as pressure transducers, and/or optical sensorssuch as cameras. In one example, a microphone may be used to detectfault conditions for pumps 74, 75, & 84 (described below with regard toFIGS. 7 & 8), as the acoustic characteristics of pumps change as theybegin to fail or are unable to operate as designed. In another example,a pressure transducer may be used to detect if the remote float device13 becomes submerged in fluid 12, such as because something ispreventing it from floating. In another example, a camera may be usedfor validation of system status and/or fault conditions that aredetected by the remote float device 13 and/or anchor device 14.

FIG. 5B illustrates an exemplary UWB positioning remote float device 13having a wired power connection. In this embodiment, there may be noneed for a battery because power may be provided over the wiredcommunication 60 link. In one embodiment, the wired communication link60 may be a RS485, and may be used to communicate with the anchordevice(s) 14.

FIGS. 5C and 5D illustrate perspective views of an exemplary UWBpositioning remote float device 13. The remote float device 13 may beformed of an air-tight housing 141 which is buoyant in fluid.Additionally, the air-tight housing 141 may be made of, or coated in, achemical resistant non-stick material to prevent corrosion and adhesionof foreign material. The remote float device 13 may also include one ormore printed circuit boards (PCB) seated within the housing 141, acapturing ring 142 for use with a guide rod 114, stabilizing fins 143 todampen movement, a counter-weight 144 to ensure proper orientation ofthe remote float device 13 in fluid, and a UWB antenna, or UWB antennaarray. The UWB antenna, or UWB antenna array, may be mounted in amultitude of different orientations within the housing 141.

FIG. 6A illustrates an exemplary UWB positioning anchor device 14 havinga wired power connection. The anchor device 14 may include, at least, aprocessor 50 operably coupled to: UWB circuitry 51 connected to multipleUWB antennas (1, N) 52; alternative RF communications 53 connected to anantenna 54; a temperature sensor 56; power management 57, wiredcommunication link 60; and external interface 61. The anchor device 14may include one or more antennas 52, depending on whether TWR, TDoA, orTWR+PDoA mode is utilized. The UWB circuitry 51 is connected to theplurality of antennas 52, allowing the calculation of position inmultiple dimensions. The UWB circuitry 51 may contain RF components,ICs, and passive components and/or a module to implement an UWB receiveror transceiver. The alternate RF communications 53 may contain RFcomponents, ICs, and passive components and/or a module to implement analternate RF communications transceiver, such as, but not limited to, aWi-Fi, BLE, and/or sub-GHz transceiver. The alternate RF communications53 transceiver may also be used as an additional RF communication linkto remote float devices 13, external control systems, smartphones, etc.The wired communication link 60 (RS485) may be used to communicate withwired remote float devices 13. The external interface 61 may be used toindicate fluid level and/or system status and may also interface with anexternal control system. The external interface 61 may include 4-20 mAoutputs, 0-5V outputs, contact closure outputs, and/or communicationinterfaces, for example. The temperature sensor 56 may be used tocompensate for the effects of temperature on individual components inthe system or in calculations performed in the processor 50. The powermanagement 57 ensures the other components in the system receiveadequate power. The power management 57 may also receive its power froman external wired power supply. The processor 50 may be suitable forexecuting algorithms and/or processing data in accordance with operatinglogic.

FIG. 6B illustrates a perspective view of an exemplary UWB positioninganchor device 14 configured for a wired power connection. The anchordevice 14 may include, at least, a water-tight housing 131, mechanicalmounting features 132, magnetic mounting features, weatherproof cableport or jack 133, one or more printed circuit boards (PCB), and a UWBantenna, or UWB antenna array. The UWB antenna, or UWB antenna array,may be mounted in a multitude of different orientations within thehousing 131.

A pump control system 76 may also be used in combination with the fluidlevel measuring devices, systems, and methods herein. The pump controlsystem 76 may control and configure the fluid measuring systems hereinand may interface these fluid level measuring systems with an externalsubsystem, such as a gauge, pumps, a pump controller, a remotemonitoring system 94, and/or an alarm. In some embodiments, the systemsherein may provide fluid level management. In this embodiment, thesystem may be programmed with a predetermined threshold so that whenfluid level reaches the predetermined threshold, or predetermined range,action may be taken to manage the fluid level, such as turning ‘on’ oractivating pumps 74, 75, & 84, and/or activating a pump control system76, as will be described with reference to FIGS. 7 and 8 below.Additionally, the pump control systems 76 herein may operate in either apump up, or a pump down, manner.

FIG. 7 illustrates an embodiment of a system for determining fluid level12 in the wet well 11 of a wastewater lift station 70 using UWBpositioning in TWR mode. In this embodiment, a wastewater lift station70 may include an underground wet well 11 having an inlet pipe 72, whichfills the wet well 11 with wastewater/fluid 12. The anchor device 14 maybe in a fixed position at the top of the wet well 11. A battery-poweredremote float device 13 may be floating on the surface of thewastewater/fluid 12 while being tethered to the weighted guide cable 77.The weighted guide cable 77 allows the remote float device 13 to freelyfloat up and down with the level of the wastewater/fluid 12, while stillpreventing the remote float device 13 from moving to an undesirableposition within the wet well 71. In other embodiments, a rigid guide rodor pipe may serve the same purpose as the weighted guide cable 77. Thebattery-powered remote float device 13 may operate in TWR mode and allowthe anchor device 14 to calculate the wastewater/fluid 12 level aspreviously described with reference to FIG. 1. The anchor device 14 maybe continually outputting the measured level of the wastewater/fluid 12(shown as dimension 7C) to the pump control system 76. When thewastewater/fluid level 12 is at a configured level, at least one of thetwo pumps 74, 75 may be turned on by the pump control system 76 to pumpthe wastewater/fluid 12 out of the wet well 11 to a higher elevation forultimate treatment at a wastewater treatment plant. When thewastewater/fluid 12 level (shown as dimension 7C) drops to a specificpredetermined level within the wet well 11, the pumps 74, 75 may then beturned off by the pump control system 76.

In an alternative embodiment, which may be applied to any of the systemsdescribed herein, the pump control system 76 may use the remainingheight within the container (shown as dimension 7B) as an input tocontrol fluid level 12 within a container 11. In this case, theremaining height within the container (shown as dimension 7B) is aninput to the pump control system 76. This would then negate the need toknow the anchor device's 14 height above the bottom of the container 11(shown as dimension 7A). The pump control system may be configured tomonitor the remaining height in the container 11 (shown as dimension 7B)and keep it within a predetermined range, or at a predetermined level.In yet another alternative embodiment, one or more pre-determined levelsor ranges can be set as control points regardless of the depth orremaining height.

FIG. 8 illustrates an embodiment of a system for determining fluid level12 in the pit 81 of a basement sump pit 80 using UWB positioning inTWR+PDoA mode. A basement sump pit may include a wet well or pit 81,which is usually underground in the basement of a home. An inlet pipe 82fills the pit 81 with groundwater/fluid 12. The anchor device 14 ismounted in a fixed position at the top of the pit 81. A wired remotefloat device 13 is floating on the surface of the groundwater/fluid 12,while still being loosely tethered to the anchor device 14 with a cable86. The cable 86 may provide both power and a wired communication linkbetween the remote float device 13 and the anchor device 14. The wiredremote float device 14 may operate in TWR+PDoA mode and allow the anchordevice 14 to calculate fluid level as previously described withreference to FIG. 4. The anchor device 14 may continually output themeasured level of the groundwater/fluid 12 to the pump control system76. When the groundwater/fluid 12 level is at, or within, apredetermined range, the pump 84 may be turned on by the pump controlsystem 76 to pump the groundwater/fluid 12 out of the pit 81 and outsideof the home. When the groundwater/fluid 12 level within the pit 81 dropsto a determined level, or range, the pump 84 may be turned off by thepump control system 76.

FIG. 9 illustrates an embodiment of a system for monitoring fluid level12 in a river 15 using UWB positioning in TWR+PDoA mode. The river water15 is generally contained within the two opposing banks 91, 92. Theanchor device 14 may be in a fixed position mounted to a pole 93 on onebank 92 of the river 15. A battery-powered remote float device 13 may befloating on the surface of the river water/fluid 12, while beingtethered to a guide rod 95 that is driven into the river bottom. Theguide rod 95 may allow the remote float device 13 to freely float up anddown with the fluid level 12 of the river 15, but still prevents theremote float device 13 from floating away. The battery-powered remotefloat device 13 may operate in TWR+PDoA mode and allow the anchor device14 to calculate the position of the remote float device 13 in multipledimensions. Knowing the remote float device's 13 position relative tothe anchor device 14 allows for calculation of the level of the riverwater/fluid 12 (shown as dimension 9A). The anchor device 14 maycontinually output the measured level of the river water/fluid 12 to aremote monitoring system 94. The remote monitoring system 94 may beconfigured to send alerts if the change in river water/fluid 12 levelpasses a predetermined threshold, such as to provide notification offlood conditions or container overflow.

FIG. 10 illustrates an exemplary embodiment of a method for measuringfluid level using UWB positioning or localization. The method mayinclude positioning at least one anchor device 14 at a fixed locationover a fluid's 12 surface, with the at least one anchor device 14having, and/or operably coupled to a UWB antenna, or UWB antenna array.At least one remote float device 13 may also be floating in the fluid 12and configured to emit RF signals. The anchor device 14 and/or a remoteprocess, and/or a processor within the anchor device 14 may then receiveat least one of the RF signals emitted by the remote float device 13.The method may further continue by generating one or more measurementsin response to receipt of the at least one RF signal between the atleast one remote float device and the at least one anchor device, aphase-difference-of-arrival (PDoA) or a combination thereof. The methodmay further continue by calculating, based upon the one or moremeasurements, at least one of: i) level of the fluid; ii) a distancebetween the at last one anchor device and the at least one remote floatdevice; and iii) an angle of the at least one remote float device. Themethod may conclude with providing a measurement of the fluid levelbased upon the calculating of the one or more measurements.

FIG. 11 illustrates an exemplary logic flow diagram for a smartphoneapplication that may communicate with a system for measuring fluid levelusing UWB positioning. Once an anchor device 14 is mounted in a fixedposition, the system may be configured to start. The first step mayinvolve the user launching a custom-developed computer and/or smartphoneapplication. The application may establish a communications link withthe anchor device 14 using the alternate RF communication link 53. Theuser may then be required to take action to put the anchor device 14 inconfiguration mode, so the alternate RF communication link 53 becomesactive. This communication link is secured using industry standardencryption and security practices. After the communication link isestablished, configuration parameters may then be entered in thecomputer and/or smartphone application and transferred to the anchordevice 14. The first configuration parameter in this embodiment may bethe position of the anchor device 14 within the fluid container 11. Onepossible method of specifying the anchor device's 14 position is byusing X and Y dimensions relative to the center the container 11, and aZ dimension, which is the height of the anchor device 14 above thebottom of the container 11. Next, a user may then determine whichexternal interface(s) 61 should be enabled. The user may be able toselect and enable interfaces such as 4-20 mA outputs, 0-5V outputs,simple contact closure outputs, and communication interfaces, forexample. The user may then pair any number of remote float devices 13 tobe used within the system. Pairing is accomplished by entering one ormore unique identification codes (IDs) of the remote float devices 13into the computer and/or smartphone application. This process may beaided by allowing the user to scan a barcode on the exterior of theremote float device 13 with the smartphone's camera, or by scanning anNFC tag within the remote float device 13, with the smartphone's NFCtransceiver. Once all configuration parameters are entered, thecommunication link is closed, and the configuration process is ended.

FIG. 12 illustrates an exemplary logic flow diagram for a possiblecommunication exchange between a remote float device 13 and an anchordevice 14. In general, the remote float device 13 may initiatecommunication whenever a trigger criteria is satisfied or met. A triggercriteria may include a rule by which one or more configured setting(s)are compared against real-time measurements or state. For example, theremote float device 13 may initiate communication in response to receiptof a message generated by the anchor device 14 or another remote floatdevice, movement of the remote float device 13, passage of apredetermined time interval or time of day, diagnostic events,low-battery conditions, high-level or low-level detection, etc. Anotherwake-up reason may be an IMU 55 event, and/or other auxiliary sensorinput event, that may indicate a stuck float condition, a rapidlychanging fluid level, or turbulence on the surface of the fluid.Furthermore, diagnostic events such as battery health state changes,temperature state changes, and other faults may also trigger a wake-upevent.

After wake-up of the remote float device 13, the remote float device 13first transmits its current state to the anchor device 14. This stateinformation may include, but is not limited to, IMU readings, batterycondition, wake-up reason, and device information such as firmwareversions. The data may be transmitted over one or more RF links in thesystem for wireless remote float devices 13 and/or over communicationlinks such as RS485 for a wired remote float devices 13.

Regardless of the communication link medium, all data over the link maybe secured using industry standard encryption and security practices.Once the remote float device's 13 status is transmitted, the remotefloat device 13 emits at least one UWB RF signal to initiate one of theoperating modes (TDoA, TWR, or PDoA) with the anchor device 14. Theanchor device 14 then calculates the level of the fluid 12. When a newfluid level is calculated, any configured external interfaces areupdated so any external control systems can act on the new fluid level.Finally, the anchor device 14 may then transmit a new remote floatdevice 13 configuration to be used during the next exchange. Thisconfiguration may include wake interval, inertial measurement unitreading thresholds for wake-up, and duration of UWB signal emission.Once the configuration is transmitted and acknowledged, the float devicegoes to sleep.

The dynamic configuration of the remote float device 13 allows theanchor device 14 to control how often the remote float device 13 wakesup. For instance, if the fluid level is changing rapidly, the system canbe configured for a shorter remote float device 13 sleep interval tosample the fluid level more often, which allows for higher resolutioncontrol of the fluid level. During periods where the fluid level is notchanging, the sleep interval may be configured to be longer to conservepower.

UWB receivers and/or transceivers are offered by semiconductor vendorssuch as NXP and Qorvo, which utilize advanced techniques to ensurerobust performance in environments where RF reflections may beproblematic, such as near fluid. RF reflections off objects and surfacesin an environment can cause erroneous distance and angle calculations inUWB applications. High receiver sensitivity and high-speed signalprocessing algorithms may be used to detect RF reflections and rejectthem. The transmitting power of an UWB transceiver may be lowered toreduce reflections and be automatically tuned for container size withintelligent algorithms. Additionally, RF performance measurements suchas received signal strength and/or signal-to-noise ratio may be used todetect RF reflections or obstructions that may affect performance.

The embodiments described herein illustrate how the present inventionprovides wide-range fluid measure capability and can measure the entirepractical depth and/or level of fluid. The use of UWB RF for distanceand position measurements exempts the need for calibration becausechanges in the environmental conditions such as the presence of dust andwater vapor will have a negligible effect on accuracy. UWB technology isrobust and will not suffer from inaccuracies caused by RF reflections.Furthermore, this system does not have any moving parts requiringservicing, nor any orifices prone to clogging, etc.

The processor and/or controller described herein may be in communicationwith memory and additional elements such as the UWB, alternative RFcommunications, power management, RS485, external interface(s), etc.Examples of the processor may include, but are not limited to, a generalprocessor, a central processing unit, logical CPUs/arrays, amicrocontroller, an application specific integrated circuit (ASIC), adigital signal processor, a field programmable gate array (FPGA), and/ora digital circuit, analog circuit, or some combination thereof.

Alternatively, or in addition, the processor and/or controller may beone or more devices operable to execute logic. The logic may includecomputer executable instructions or computer code stored in memory thatwhen executed by the processor, cause the processor to perform theoperations described for the anchor device(s), float device(s), and/orthe system. The computer code may include instructions executable withthe processor and/or controller.

Memory may be any device for storing and retrieving data or anycombination thereof. The memory may include non-volatile and/or volatilememory, such as a random-access memory (RAM), a read-only memory (ROM),an erasable programmable read-only memory (EPROM), or flash memory.Alternatively, or in addition, the memory may include a solid-statedrive or any other form of data storage device. Memory (as describedabove) is generally referred to herein as data storage 59.

The “blocks” in the figures and related discussion may refer tohardware, or a combination of hardware and or software. For example, ablock may refer to memory, a processor and/or instructions executable bythe processor. Alternatively, or in addition, the blocks may refer tocircuitry.

At least some of the system and its logic and data structures may bestored on, distributed across, or read from one or more types ofcomputer readable storage media (for example, as logic implemented ascomputer executable instructions or as data structures in memory).Examples of the computer readable storage medium may include a harddisk, a flash drive, a cache, volatile memory, non-volatile memory, RAM,flash memory, or any other type of computer readable storage medium orstorage media. The computer readable storage medium may include any typeof non-transitory computer readable medium.

The processing capability of the system may be distributed amongmultiple entities, such as among multiple processors, controllers, andmemories, optionally including multiple distributed data acquisition andprocessing systems. Parameters, databases, and other data structures maybe separately stored and managed, may be incorporated into a singlememory or database, may be logically and physically organized in manydifferent ways, and may implemented with different types of datastructures such as linked lists, hash tables, or implicit storagemechanisms. Logic, such as programs or circuitry, may be combined orsplit among multiple programs, distributed across several memories andprocessors, and may be implemented in a library, such as a sharedlibrary (for example, a dynamic link library (DLL).

Furthermore, and in at least some embodiments, exemplary systems of thepresent disclosure are configured to capture two-way communication ofeach device 13, 14 within said system, such as between the anchordevices 14 and remote float devices 13. As such, and in variousembodiments, RF transceivers 53 used in the system, and two-way rangingis used to calculate time of flight. In at least one embodiment, eachdevice 13, 14 within the system comprises a transceiver 53. RF signals,as referenced herein, have data embedded that is used for thetime-of-flight calculations (referred to herein as packets). In at leastsome embodiments, the remote float device 13 comprises achemical-resistant coating to prevent corrosion and/or adhesion offoreign material thereon. The present disclosure also includesdisclosure whereby the processor 50 is configured to adjust the intervalat which the RF signals are emitted by the remote float device 13 basedon a rate of change of the level of the fluid 12 to optimize batterylife. In at least some embodiments, the at least one remote float device13 or the at least one anchor device 14 is configured to optimize RFtransmitting power to reduce reflections and extend battery life.

In at least some embodiments, the processor 50 is further configured tosignal a pump control system 76 to pump the fluid in response toremaining space in the container 11 being greater than or less than athreshold value. In at least some embodiments, the processor 50 isfurther configured to notify an external control system that the levelof the fluid 12 has changed. In at least some embodiments, the processor50 is further configured to notify an external control system inresponse to receipt of a message from the at least one anchor device 14or the at least one remote float device 13. In at least someembodiments, the processor 50 is also in operable communication with theat least one anchor device 14 or the at least one remote float device 13using an alternate RF communications 53 comprising Wi-Fi, BLE, orsub-GHz antenna. In at least some embodiments, the at least one remotefloat device 13 is further configured to detecting activity of pumps 74,75 of the pump control system 76 by analyzing acoustic characteristicsfrom a microphone 56 positioned relative to the pumps 74, 75, andtransmitting data from the microphone 56 to the processor 50. In atleast some embodiments, the at least one remote float device 13 isfurther configured to operate a pressure transducer 53 to detect acondition of the at least one remote float device 13 as being submergedunder the surface of the fluid. In at least some embodiments, the atleast one remote float device 13 further comprises at least oneauxiliary sensor 56 selected from the group consisting of anaccelerometer, a gyroscope, and a magnetometer. In at least someembodiments, the at least one remote float device 13 further comprisesan accelerometer, the at least one remote float device 13 furtherconfigured to operate the accelerometer to detect a condition of the atleast one remote float device 13 as not being level with the surface ofthe fluid.

In at least some embodiments, the processor 50 is further configured toobtain telemetry data and instruct said telemetry data to be storedwithin an external data storage system. In at least some embodiments,the telemetry data is selected from the group consisting of fluid level,fluid overflow, fluid temperatures, stored power levels, and microphonedata.

While various embodiments of devices and systems and methods for usingthe same have been described in considerable detail herein, theembodiments are merely offered as non-limiting examples of thedisclosure described herein. It will therefore be understood thatvarious changes and modifications may be made, and equivalents may besubstituted for elements thereof, without departing from the scope ofthe present disclosure. The present disclosure is not intended to beexhaustive or limiting with respect to the content thereof.

Further, in describing representative embodiments, the presentdisclosure may have presented a method and/or a process as a particularsequence of steps. However, to the extent that the method or processdoes not rely on the particular order of steps set forth therein, themethod or process should not be limited to the particular sequence ofsteps described, as other sequences of steps may be possible. Therefore,the particular order of the steps disclosed herein should not beconstrued as limitations of the present disclosure. In addition,disclosure directed to a method and/or process should not be limited tothe performance of their steps in the order written. Such sequences maybe varied and still remain within the scope of the present disclosure.

1. A system for measuring a fluid level, comprising: at least one anchordevice having at least one radio-frequency (RF) antenna positioned at afixed location over a surface of a fluid to be measured; at least oneremote float device configured to emit at least one RF signal andconfigured to float on the surface of a fluid to be measured; and aprocessor in operable communication with the at least one anchor device,the processor configured to: receive the at least one RF signal from theat least one RF antenna, emitted from the at least one remote floatdevice; analyze the at least one RF signal from the at least one RFantenna; measure a time-of-flight of the at least one RF signal betweenthe at least one remote float device and the at least one anchor device;and calculate a location of the at least one remote float device basedupon the analyzed at least one RF signal received by the at least one RFantenna, wherein the location of the at least one remote float devicecorresponds to a level of the fluid.
 2. The system of claim 1, whereinthe processor is further configured to: calculate a level of the fluidbased on the fixed location of the at least one anchor device and thetime-of-flight of the at least one RF signal.
 3. The system of claim 2,wherein the processor is further configured to: calculate location ofthe at least one remote float device based on the time-of flight of theat least one RF signal and the fixed location of the at least one anchordevice.
 4. The system of claim 1, wherein the processor is furtherconfigured to: calculate the position of the at least one remote floatdevice in a plurality of dimensions based on the time-of-flight and thephase-difference-of-arrival.
 5. The system of claim 1, wherein theprocessor is further configured to: signal a control system in responseto the fluid level being greater than or less than a threshold value. 6.A system for measuring a fluid level, comprising: at least one anchordevice having a first radio-frequency (RF) transceiver, coupled to atleast one first RF antenna, positioned at a fixed location over asurface of a fluid to be measured; at least one remote float devicehaving a second radio-frequency (RF) transceiver, coupled to at leastone second RF antenna, configured to float on the surface of the fluidto be measured; the at least one first RF antenna or the at least onesecond RF antenna configured to receive the at least one RF signal; thetransceiver configured to extract packets from the at least one RFsignal; a processor in operable communication with at least one of thefirst RF transceiver and the second RF transceiver, the processorconfigured to: receive the at least one packet from the second RFtransceiver, transmitted from the at least one remote float device;analyze the at least one packet from the second RF transceiver; measurea time-of-flight of the at least one RF signal between the at least oneremote float device and the at least one anchor device using the RFpackets; calculate a location of the at least one remote float devicebased upon the time-of-flight, wherein the location of the at least oneremote float device corresponds to a level of the fluid.
 7. The systemof claim 6, wherein the at least one remote float device furthercomprises a chemical-resistant coating to prevent corrosion and adhesionof foreign material to the remote float device.
 8. The system of claim6, wherein the at least one remote float device further comprises amechanical housing selected from the group consisting of an air-tighthousing, a capture ring, a stabilizing fin, and a counter-weight.
 9. Thesystem of claim 6, wherein the processor is further configured to:adjust an interval at which the RF signals are emitted by the at leastone remote float device based on a rate of change of the level of thefluid.
 10. The system of claim 6, wherein the at least one remote floatdevice or the at least one anchor device is configured to optimize RFtransmitting power to reduce reflections and extend battery life. 11.The system of claim 6, wherein the processor is further configured to:signal a pump control system to pump the fluid in response to remainingspace in the container being greater than or less than a thresholdvalue.
 12. The system of claim 6, wherein the processor is furtherconfigured to: notify an external control system that the level of thefluid has changed.
 13. The system of claim 6, wherein the processor isfurther configured to: notify an external control system in response toreceipt of a message from the at least one anchor device or the at leastone remote float device.
 14. The system of claim 11, wherein the atleast one remote float device is further configured to: detect activityof pumps of the pump control system by analyzing acousticcharacteristics from a microphone positioned relative to the pumps; andtransmit data from the microphone to the processor.
 15. The system ofclaim 6, wherein the at least one remote float device is furtherconfigured to: operate a pressure transducer to detect a condition ofthe at least one remote float device as being submerged under thesurface of the fluid.
 16. The system of claim 6, wherein the at leastone remote float device further comprises at least one auxiliary sensorselected from the group consisting of an accelerometer, a gyroscope, anda magnetometer.
 17. The system of claim 6, wherein the at least oneremote float device further comprises an accelerometer, the at least oneremote float device further configured to: operate the accelerometer todetect a condition of the at least one remote float device as not beinglevel with the surface of the fluid.
 18. The system of claim 6, whereinthe processor is further configured to obtain telemetry data andinstruct said telemetry data to be stored within an external datastorage system.
 19. The system of claim 18, wherein the telemetry datais selected from the group consisting of fluid level, fluid overflow,fluid temperatures, stored power levels, and microphone data.
 20. Amethod of operating a system for measuring a fluid level, the methodcomprising the steps of: floating at least one remote float device on asurface of a fluid to be measured, the at least one remote float devicecomprising at least one radio-frequency transceiver configured totransmit and receive radio-frequency (RF) signals; positioning at leastone anchor device at a fixed location over the surface of the fluid tobe measured, the at least one anchor device comprising at least oneradio-frequency transceiver configured to transmit and receive RFsignals; capturing transmission and reception timestamps of the RFsignals transmitted between the at least one anchor device and the atleast one remote float device; exchanging the transmission and receptiontimestamps between the at least one anchor device and the at least oneremote float device in a two-way ranging round to calculate atime-of-flight of the RF signals; and calculating a distance betweeneach at least one anchor device and the at least one remote float devicebased upon the time-of-flight of the RF signals.